by Mary Whiton Calkins

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: with intensity (and with bigness) is called sensation. Some psychologists treat the sensation as unit of perception and describe the qualities, — of color, pitch, and the like, — the intensities — brightnesses, loudnesses, and so on — and the extensities, not as sensational elements but as attributes of sensation.29 The succeeding chapter will speak further of fusions. In the meantime, a word must be said of the physiological conditions of perception and imagination. In ordinary perception, some sensational elements are excited through stimulation of end-organs (that is, 'peripherally' excited), whereas all sensational elements in imagination are conditioned by brain excitation ('centrally' excited). So, when I imagine the Theatre of Dionysos, at Athens, only my occipital lobe is excited, but when I look out at Symphony Hall, my retina is excited as well; when I imagine the flute-like song of the hermit thrush, only my temporal lobe is .excited; but when I hear the telephone bell ring, the inner organs of my cochlea are in vibration. It should be noted that this account of the physiological condition of perception does not hold in the case of the hallucination. The hallucination, like the illusion, is a perception which does not directly correspond with any external object. Both hallucination and illusion are perception — that is, involuntary and predominantly sensational experience, reflectively attributed to other people, of objects regarded as impersonal and external. But whereas the illusion includes peripherally excited elements, a hallucination contains only centrally excited sense-elements. The dream or deliriumimage of a ghost, for example, is a hallucination, because it is not excited by any external object, whereas the traditional confusion of window-curtain with g...